code: def test_no_matched_index(self):
      with self.assertRaisesRegex(
          ValueError, "Index names must be exactly matched"
      ):
          ps.DataFrame({"a": [1, 2, 3]}).set_index("a") + ps.DataFrame(
              {"b": [1, 2, 3]}
          ).set_index("b")
  
imports: import unittest
  import pandas
  from pyspark import pandas
  from pyspark.pandas.config import set_option, reset_option
  from pyspark.testing.pandasutils import PandasOnSparkTestCase
  from pyspark.testing.sqlutils import SQLTestUtils
label_desc: Use image node_id 12 for calling the BasicMixin obj's underlying member method code with example usage: obj.test_no_matched_index() without return types